This invention relates to guide mechanisms for use in drop loading articles into the cellular compartments of cartons and, more particularly, for loading bottles into such cartons by way of the so-called drop loading technique.
The technique itself is well known; for example, U.S. Pat. No. 3,788,034 (Hartness et al) discloses a grid set for use on a bottle loading machine. The Hartness arrangement includes means for positioning bottles in aligned rows above the grid set and means for positioning empty cases below the grid set to receive the bottles. The grid set incorporates drop loading fingers which engage the sides of the bottle as it is dropped into a carton. The loading fingers aid in properly opening the individual compartments of the carton to be loaded, direct the bottles into those compartments and retard the acceleration experienced by the bottles during drop loading so that the bottles are deposited gently in the carton. However, a persistent problem in mechanisms of this type has been that of avoiding damage to the upstanding partitions defining the cells of the carton. The damage normally occurs when the base of the bottle strikes the partition. The problem is accentuated in the case where an empty carton presented for loading is warped or not set up in square condition.
The Hartness construction utilizes a set of four loading fingers for each carton cell. The fingers of each set have angled flange portions which extend outwardly to engage the corners of the carton cell to ensure that the cell is extended properly for receiving a bottle. However, in many basket-style cartons, the partition construction is such that the top edge of a partition extends horizontally from the longitudinal medial partition outwardly for a distance which is at least equal to the transverse width of the carton cell, whereafter the partition is cut away so that the top edge is inclined downwardly towards the adjacent side wall of the carton. The transition between the horizontal and inclined portions of the partition top edge forms a shoulder which can present an obstruction to a bottle being inserted in an adjacent cell. It is not normally practical to redesign the shoulder since to do so would provide inadequate material for preventing contact between bottles in those adjacent cells. The flanges of the loading fingers in the Hartness construction are not designed to give adequate protection to the partitions, particularly in the shoulder region, during the loading operation.
U.S. Pat. No. 3,908,339 (Kennedy et al) discloses a guide mechanism which went some way towards alleviating the problem of cell misalignment by providing a set of four essentially rigid spring biased drop loading fingers for each cell rather than flexible drop fingers used in some previous constructions. However, these known drop fingers also do not succeed in achieving an acceptable degree of protection against damage to the cell partitions.
U.S. Pat. No. 4,171,603 (Wiseman) discloses a grid mechanism for use in drop loading articles. Wiseman recognizes that the space between the bottle wall and the associated cell wall of the carton is extremely limited, and states that the drop loading fingers in order to be present in the cell when the bottle is situated therein must be either located at the corners of the cell or, if located parallel to the cell walls, be extremely thin. The solution offered by the Wiseman disclosure is to provide only a pair of opposed guide members for each cell and this also does not achieve adequate protection for the cell partitions.